How to Grow Crepe Myrtles: Sizes, Pruning and Care

Good crepe myrtle care starts with something that happens before you ever pick up the pruners: choosing a variety that actually fits the space.

Crepe myrtles (Lagerstroemia indica and hybrids) are some of the most recognizable flowering plants in Southern landscapes. They handle Georgia heat, produce colorful summer flowers, develop attractive bark as they mature, and many varieties add good fall color too.

The trouble usually starts when a 20-foot crepe myrtle gets planted in a space meant for an 8-foot shrub.

Quick Answer

Crepe myrtles grow and bloom best in full sun with well-drained soil. Water newly planted crepe myrtles consistently while the roots become established, but don’t keep the soil soggy.

Most crepe myrtles need very little pruning. If pruning is necessary, do it in late winter or early spring before new growth begins. Remove dead, crossing, crowded, or unwanted branches instead of cutting all the main trunks back to stubs.

Most importantly, choose a variety whose mature size fits the location.

Crepe Myrtle Care at a Glance

Choose the Right Size Crepe Myrtle First

This may be the most important part of crepe myrtle care.

Crepe myrtles range from compact shrubs only a few feet tall to large flowering trees that can reach 20 to 30 feet or more.

That means you should choose the variety for the location instead of planting whichever color catches your eye and figuring out the size problem later.

Planting a large tree-form crepe myrtle next to a porch or underneath a low roof is a little like buying a full-size pickup truck and trying to park it in a broom closet.

It may fit for a while.

Eventually, something has to give.

Here are several popular varieties and their approximate mature sizes:

These sizes are general guidelines. Mature size can change somewhat with climate, growing conditions, cultivar, and age.

Always check the mature height and width before planting.

Where Should You Plant a Crepe Myrtle?

Crepe myrtles love sunlight.

For the strongest growth and best flowering, choose a location receiving at least six hours of direct sun each day.

Here in Georgia, we often talk about protecting certain shrubs from our brutal afternoon sun.

Crepe myrtle is different.

This is one plant that generally wants the sunshine.

Too much shade can cause:

• Fewer flowers
• Thin or weak growth
• Poorer air circulation
• More disease problems
• A plant that stretches toward available light

The University of Georgia Cooperative Extension also recommends full sun for strong growth and flowering and notes that heavy shade can increase problems such as powdery mildew and sooty mold.

If you’re looking for other plants that tolerate our bright Southern sun, see our guide to the best flowering shrubs for full sun in Georgia.

Give Crepe Myrtles Enough Room

Don’t judge spacing by the plant sitting in the nursery container.

Think about what it will look like five, ten, or even twenty years from now.

Avoid squeezing a large crepe myrtle:

• Against the house
• Under power lines
• Between a sidewalk and driveway
• Directly against another large shrub
• Into a narrow foundation bed

Giving the plant enough space means less pruning later and allows its natural branching structure to develop.

A properly sized crepe myrtle shouldn’t need to be chopped down every winter just to keep it from swallowing the house.

How to Plant a Crepe Myrtle

Planting correctly gives a new crepe myrtle a much better start.

Dig the planting hole wider than the root ball, but don’t make it unnecessarily deep.

The top of the root ball should generally remain level with or slightly above the surrounding ground.

That point matters here in Georgia because our red clay can hold a surprising amount of water.

A deeply planted root ball sitting in a wet clay hole can struggle even when the plant looks perfectly healthy when it leaves the nursery.

When Planting:

1. Dig the hole wider than the root ball.
2. Remove the plant from its container.
3. Check for circling roots.
4. Gently loosen tightly wrapped outer roots.
5. Set the root ball at the proper height.
6. Backfill mainly with the soil removed from the hole.
7. Water the entire root ball thoroughly.
8. Add mulch around the root area.
9. Keep mulch away from the trunks.

For a more detailed look at how we approach planting, see How to Plant Flowering Shrubs in Your Landscape.

Growing Crepe Myrtles in Georgia Red Clay

Crepe myrtles can grow well in clay soil as long as the planting area drains.

Clay itself isn’t automatically bad soil.

The bigger problem is a low or compacted area where water sits around the roots after rain.

Before planting, look at the site after a heavy rain.

If water remains standing for long periods, planting a crepe myrtle there without addressing the drainage may lead to root problems later.

Don’t try to solve poor drainage by simply digging an extra-deep hole.

In heavy clay, that can create a bowl that collects water around the root ball.

Wide and properly drained is better than deep.

How Often Should You Water a Crepe Myrtle?

Newly planted crepe myrtles need regular watering while their roots become established.

That doesn’t mean watering automatically every day.

Check the soil.

The original root ball can dry even when the surrounding soil still feels damp. The opposite can happen too: the surface may appear dry while the clay underneath is still holding plenty of moisture.

Water slowly enough to wet the entire root ball.

The University of Georgia Cooperative Extension’s crepe myrtle guide recommends thorough watering at planting and regular watering during establishment when rainfall is lacking. Established plants become considerably more drought tolerant, although watering during prolonged dry weather can improve flowering.

If you’ve ever had a newly planted shrub struggle even though you thought you were watering correctly, our guide explaining why new landscape plants die goes deeper into root balls, watering, planting depth, and Georgia clay.

Mulch Around Crepe Myrtles

A 2-to-3-inch layer of organic mulch can help:

• Slow moisture loss
• Reduce weeds
• Moderate soil temperature
• Keep grass away from the root zone
• Protect the trunk from mowers and string trimmers

Spread mulch outward rather than piling it upward.

Never build a mulch volcano around the trunks.

Leave several inches of open space immediately around the base.

Mulch touching the bark can hold moisture where you don’t want it.

For more details, our guide to the best mulch for shrubs explains the mulch types we use, proper depth, and common mulching mistakes.

When Should You Fertilize Crepe Myrtles?

Crepe myrtles usually don’t need heavy feeding.

In fact, too much nitrogen can encourage a lot of leafy growth without giving you more flowers.

If an established plant is growing normally and blooming well, don’t assume it needs fertilizer just because spring arrived.

If growth is poor, a soil test is a better starting point than guessing.

When fertilizer is needed, a light application in spring is usually better than repeatedly feeding throughout the season.

Avoid fertilizing heavily late in the year because you don’t want to encourage tender new growth heading into cold weather.

When Should You Prune Crepe Myrtles?

Crepe myrtles flower on new growth produced during the current season.

If pruning is needed, late winter or early spring before new growth begins is generally the best time.

But here’s the part that’s often missed:

Crepe myrtles do not need to be heavily pruned every year in order to bloom.

A well-placed crepe myrtle may need very little pruning.

The University of Georgia Cooperative Extension specifically notes that crepe myrtles don’t require pruning to flower and recommends limited or no pruning when possible.

Our guide to when to prune flowering shrubs explains why summer-blooming plants such as crepe myrtles are different from shrubs that flower on last year’s growth.

How to Prune a Crepe Myrtle Correctly

Before making a cut, ask why you’re making it.

Good reasons include removing:

• Dead branches
• Broken branches
• Diseased growth
• Crossing branches
• Branches growing toward the center
• Small unwanted shoots
• Suckers growing from the base
• Branches interfering with a structure or walkway

You can also lightly thin crowded growth to improve the shape and airflow.

Avoid turning pruning into an annual effort to reduce a large tree to half its natural height.

If you have to perform major surgery every winter just to make the crepe myrtle fit, the variety is probably too large for the location.

Please Don’t Commit “Crepe Murder”

You’ve probably seen it.

A beautiful mature crepe myrtle gets cut back until nothing is left except several thick trunks ending in large stubs.

Then long, weak shoots grow rapidly from those cuts.

This severe topping is commonly called crepe murder.

It isn’t necessary for flowering.

Heavy topping can:

• Destroy the plant’s natural shape
• Produce clusters of weak shoots
• Create large pruning wounds
• Encourage excessive sucker growth
• Hide the beautiful branching structure
• Create more pruning work every year

UGA warns against this aggressive pruning practice and notes that limited pruning produces a more natural and attractive plant.

The better solution is to choose a variety that fits the available space.

Can You Grow a Crepe Myrtle as a Tree?

Yes.

Many larger varieties can be trained into an attractive multi-trunk or tree form.

Choose several strong main trunks and gradually remove unwanted shoots from the base.

Lower branches can be removed over time to expose more of the trunks and attractive bark.

Don’t try to create the final tree shape in one afternoon.

Gradual pruning usually produces a much more natural result.

Should You Deadhead Crepe Myrtles?

You don’t have to deadhead a crepe myrtle.

Some smaller varieties may produce another flush of flowers after spent flower clusters are removed, especially when the growing season is long.

But on large trees, deadheading quickly becomes more work than it’s worth.

We wouldn’t climb around in a mature crepe myrtle just to remove old flowers.

Let the plant do its thing.

Why Isn’t My Crepe Myrtle Blooming?

If a crepe myrtle isn’t flowering well, start with the basics.

Not Enough Sun

This is one of the first things to check.

Crepe myrtles need plenty of direct sunlight for their best flowering.

Too Much Nitrogen

A plant producing lots of dark green leaves but few flowers may be getting too much nitrogen.

This sometimes happens when lawn fertilizer repeatedly reaches the root zone.

Heavy Pruning

Severe pruning can create a lot of fast vegetative growth.

Although crepe myrtles bloom on new wood, constantly forcing the plant to rebuild itself isn’t the best road to a naturally beautiful tree.

Drought

Established crepe myrtles tolerate dry weather fairly well, but severe drought during summer can reduce flowering.

Wrong Variety for the Location

A stressed plant crammed into a poor site may never perform as well as one planted where it naturally fits.

Common Crepe Myrtle Problems

Crepe myrtles are generally tough plants, but they’re not completely trouble-free.

Powdery Mildew

Powdery mildew can create a white or gray powdery coating on leaves, shoots, and flower buds.

It tends to be worse where airflow is poor or plants receive too much shade.

UGA identifies powdery mildew as one of the more important crepe myrtle diseases in Georgia. Resistant cultivars and good placement can reduce problems.

Cercospora Leaf Spot

Cercospora leaf spot can cause dark spots followed by yellowing and premature leaf drop.

Warm, humid Southern weather can favor leaf disease.

Good air movement and selecting resistant varieties can help.

Aphids and Sooty Mold

Aphids feed on the plant and produce a sticky substance called honeydew.

A dark fungus called sooty mold can then grow on that honeydew, leaving foliage looking black or dirty.

The black coating isn’t usually the original problem.

The insects producing the honeydew are what you need to investigate.

What We Look for Before Planting a Crepe Myrtle

Here in Dallas, Georgia, we’d rather prevent a maintenance problem than spend years fixing one.

Before planting, look at:

• How many hours of direct sun the location receives
• How the soil drains after rain
• The mature height of the cultivar
• The mature width
• Distance from the house
• Distance from pavement
• Overhead power lines
• Nearby trees
• Room for natural branching

That five-minute check can save years of unnecessary pruning.

Best Crepe Myrtle Care Tips for Georgia

For our hot Southern growing conditions, keep these basics in mind:

1. Give the plant plenty of sun.
2. Choose the mature size before choosing the flower color.
3. Plant the root ball at the proper depth.
4. Make sure Georgia clay drains after rain.
5. Water the complete root ball during establishment.
6. Mulch 2 to 3 inches deep without covering the trunks.
7. Don’t over-fertilize.
8. Prune only when there’s a reason.
9. Never top a crepe myrtle just because everyone else does.
10. Give the plant room to develop its natural shape.

Frequently Asked Questions

Do crepe myrtles need full sun?

Yes. Crepe myrtles generally flower best in full sun. Aim for at least six hours of direct sunlight each day.

When should I prune a crepe myrtle?

If pruning is necessary, late winter to early spring before new growth begins is generally the best time.

Do you have to prune crepe myrtles every year?

No. Crepe myrtles don’t require annual pruning to produce flowers. A properly placed plant may need little more than removal of dead, damaged, crossing, or unwanted branches.

How often should a newly planted crepe myrtle be watered?

There’s no perfect calendar schedule. Water thoroughly after planting and continue checking the original root ball while the plant establishes. Water when needed based on rainfall, temperature, soil, drainage, and how quickly the root ball is drying.

Are crepe myrtles drought tolerant?

Established crepe myrtles are fairly drought tolerant, but prolonged dry weather can reduce growth and flowering.

Why does my crepe myrtle have black leaves?

Black leaves are often caused by sooty mold growing on honeydew produced by insects such as aphids. Look closely for the insect problem rather than treating the black coating alone.

Will a crepe myrtle grow in Georgia clay?

Yes, provided the site drains well. Avoid low areas that remain waterlogged after rain.

How tall do crepe myrtles grow?

It depends heavily on the cultivar. Some dwarf varieties stay around 3 to 5 feet tall, while large tree forms can reach 20 to 30 feet or more.

Final Thoughts

Good crepe myrtle care isn’t complicated.

Give the plant plenty of sunlight, choose a variety that fits the available space, plant it correctly, keep it watered while the roots establish, and resist the urge to chop it down every winter.

Most of the problems we see with crepe myrtles can be traced back to the same few things: the wrong location, the wrong size plant, too much fertilizer, poor drainage, or unnecessary pruning.

Get those basics right and a crepe myrtle can provide summer flowers, colorful fall foliage, beautiful bark, and winter structure for many years.

If you’ve got a hydrangea or flowering-shrub question, come find Bobby & Lynn’s Plant Farm on Facebook. We’re always glad to talk plants.